Review of recent confinement studies in heliotron E and introduction of L=1 helical axis heliotron device (heliotron J)

The variation of the profiles and the confinement properties are studied in Heliotron E using NBI and ECR heating under the boronized wall condition. With high power NBI heating, the peaked density and the peaked ion temperature were realized in the medium density region. For ECH dominant plasma, the density profile was flattened in most cases because of the density 'pumping-out' mechanism. The confinement property was changed by achieving the high ion temperature mode. The compatibility of the good confinement of the high energy particles and the MHD stability is preferable for the fusion devices. For the investigation of these issues, we are constructing the new helical axis heliotron device. One continuous helical coil is used instead of modular coils for the assurance of the accessibility for the heating and diagnostic devices. There are two types of the toroidal coils are equipped for the control of the bumpy component of the magnetic field for the reduction of transport loss